The sociology of friendship, groups, and church size

Small groups (like home Bible studies, Care Groups, and the like) have an upper size limit of 10-15, depending on the people involved. The reason is obvious, and it’s pure sociology. We can only relate meaningfully to a small group of people. Beyond that size, relational dynamics get too complex and we naturally sub-divide into smaller “groups within the group”.

Churches without associate program staff rarely grown beyond 200. The reasons are more complex, but sociology also plays a big role.

Listen to what John Agno has to say about the sociology of groups, and think about what this means for churches:

According to “The Tipping Point” by Malcolm Gladwell, to be someone’s best friend requires a minimum investment of time. More than that, it takes emotional energy. Caring about someone deeply is exhausting. At a certain point, at somewhere between 10 to 15 people, we begin to overload. Mostly, it’s a question of our available time and energy.

For example, if you belong to a group of twenty people, there are 190 two-way relationships to keep track of: 19 involving yourself and 171 involving the rest of the group. That’s a twentyfold increase in the amount of information processing needed to ‘know’ the other members of the group. Even a relatively small increase in the size of a group, creates a significant additional social and intellectual burden.

The figure of 150 seems to represent the maximum number of individuals with whom we can have a genuinely social relationship, the kind of relationship that goes with knowing who they are and how they relate to us. To have more than 150 people in a group reduces the ability of each member to be sufficiently familiar with each other that they can work together as a functional unit.

Above 150, you have to impose complicated hierarchies and rules to command loyalty and cohesion. Below 150, it is possible to achieve these same goals informally based upon personal loyalties and direct person-to-person contacts.

When things get larger than 150, people become strangers to one another. When your group gets bigger than 150, you begin to get two or three sub-groups or clans within the larger group. Above 150 people, there begins to be structural impediments to the ability of the group to agree and act with one voice.

How the 150 number applies to churches gets complicated, because church size is also heavily affected by facility space, the nature of the church programs and organizational structure, and the leadership and communication skills of the pastor. If nothing else, it’s helpful to keep in mind that people gravitate to a medium sized “communities” (ranging from 40-75) in churches, regardless of the worship attendance of the church. This is because people probably have 50 to 100 people outside the church who already play a key role in their lives … and if the social limit of most people is about 150, that leaves space for 40-75.